Weight loss, especially in the belly, is key to improved blood vessel function. The improved blood flow was noted regardless of whether the pounds were shed from a low-fat or low-carb diet.
Though participants following the low-carb diet lost an average of 10 pounds more, both resulted in improved blood vessel function, which can improve cardiovascular health.
Kerry J. Stewart, lead investigator and a professor of medicine at the Johns Hopkins University School of Medicine and director of clinical and research exercise physiology at the Johns Hopkins Heart and Vascular Institute, said the study demonstrated that vessel improvement was directly linked to the amount of belly fat lost, regardless of which diet was followed.
Stewart said this is important since concerns have been expressed about the low-carb diet’s impact on the heart since it involves consuming more fat.
During the study researchers followed 60 men and women who weighed an average of 215 pounds at the beginning of the study. Half followed a low-carb diet and half went on a low-fat diet. The groups consumed a similar amount of calories each day, and all engaged in moderate physical activity.
They evaluated blood vessel health before and after the weight loss program by constricting circulation with a blood pressure cuff for five minutes and measuring the amount of blood that reached the fingertips before, during and after the artery was constricted. Investigators found that participants who lost more belly fat had better blood flow, suggesting better blood vessel function.
Those following the low-carb diet lost an average of 28.9 pounds as compared to 18.7 pounds among those on the low-fat diet. Stewart said patients following the low-carb diet lost more weight at a faster pace because eating more carbohydrates while dieting can slow the rate of body fat loss.
Researchers said the findings suggest weight loss with exercise can improve overall vascular health. They also suggested following a low-carb diet to lose weight and improve vascular health rather than the traditionally-recommended low-fat diet.
Results of the study were presented March 13 at the American Heart Association’s Epidemiology and Prevention/Nutrition, Physical Activity and Metabolism 2012 Scientific Sessions. Preliminary study findings were first reported in June 2011 at the annual meeting of the American College of Sports Medicine in Denver.
Coronary artery disease is the leading cause of death in the United States and in the rest of the world. Estimates point to almost one half of all middle aged men and one third of all middle aged women in the United States developing some form of CAD. The primary symptom of angina, commonly known as chest pain, occurs when the artery is almost completely blocked.
Plaques made up of cholesterol and fibrous tissue lodge in the walls of the arteries that supply blood to the heart. Slow growth of the plaques can cause chest pain as they restrict blood flow to the heart muscle, and complete closure or rupture of the plaque can cause a myocardial infarction, commonly known as a heart attack, with resulting disability or death. CAD is primarily a disease of diet and habits, with the greatest risk factors coming from smoking, high blood pressure, high cholesterol, and diabetes.